Then I re-tested. Before installing, the live session can access the repositories, but after trying the netinstall installation, the access to repositories fails:
# pacman -Syy
:: Synchronizing package databases...
error: failed to update build (no servers configured for repository)
error: failed to update core (no servers configured for repository)
error: failed to update main (no servers configured for repository)
error: failed to update apps (no servers configured for repository)
error: failed to synchronize any databases
error: failed to init transaction (no servers configured for repository)
#
So I thought it was live session error.
On the other hand, I understand your reasons for removing the netinstall, but I worry a lot, I want/would a way to select/deselect software for make a minimal installation.